Carl Icahn arriving at the 32nd annual New York City Police Foundation Gala in New York in October 2012. / Henny Ray Abrams, AP

by USA TODAY

by USA TODAY

The financial news air waves heated up Friday afternoon as billionaire investors Carl Icahn and Bill Ackman engaged in an extended verbal smackdown after a recent drop in the stock price of Herbalife (HLF), a nutritional supplements company.

Bill Ackman appeared on CNBC about his decision to short-sell the shares of HerbaLife, accusing the company of being "a well-managed pyramid scheme." He stood to make millions of dollars by shorting the company's stock, which is a bet that company's stock is headed for a huge price drop.

HerbaLife's stock peaked at $70.32 a share in April 2012 and then plunged to just over $42 a share the next month and a half. In mid-December, the shares were trading at $45 a share and then plunged to just over $26 a share after Ackman revealed his massive short-sale position in the stock

Icahn called CNBC after the Ackman interview Friday, and the financial news network aired a live interview with the longtime investor about Ackman's remarks on HerbaLife and other stocks.

"Ackman is a liar," Icahn said on CNBC Friday afternoon. "He's got one of the worst reputations on Wall Street."

Icahn also alleged that Ackman unfairly and deliberately tries, and often succeeds, in forcing companies' stock prices down by publicly revealing when he has taken a huge short position in a specific stock.

"I've really about had it with this guy," Icahn said. "He's like the crybaby in the schoolyard."